Related Experiment Video
Updated: Jun 23, 2026

Advancing Dyslexia Assessment in Children Through Computerized Testing
Published on: August 16, 2024
Statistical implications of the choice between a dichotomous or continuous trait in studies of interobserver
1Department of Epidemiology and Biostatistics, The University of Western Ontario, London, Ontario N6A 5C1, Canada.
Abstract:
A frequently occurring question in the planning of studies is whether to measure the trait of interest on a continuous or dichotomous scale. An issue potentially relevant to this question centers around the resulting reliability of the measure. Assuming the continuous trait has a normal distribution, we quantify the effect of this decision on the overall number of subjects required to test whether a population reliability coefficient equals a specified criterion value. Two distinct cases are explored: the choice between a continuous response and a truly dichotomous response, and the case in which an inherently continuous response is dichotomized. In both cases, and particularly in the second, the loss of power associated with measuring the trait on a dichotomous scale is shown to be always severe and frequently prohibitive.
Related Concept Videos
Odds Ratio
Statistical Analysis: Overview
One of the most commonly used statistical quantifiers is the mean, which is the ratio between the sum of the numerical values of all results and the...
Test for Homogeneity
Biostatistics: Overview
Discrete variables are...
Choosing Between z and t Distribution
Comparing Experimental Results: Student's t-Test
